Bump Kubernetes version from 1.7.3 to 1.7.4

Tweak setup document about set env

Implements: blueprint upgrade-kubernetes

Change-Id: Ib6c25c9affcf7020aaf127220dad7e07f9b518ff
Signed-off-by: Kevin Zhao <kevin.zhao@arm.com>

devstack/plugin.sh

@@ -97,15 +97,15 @@ gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg
 EOF'
         sudo setenforce 0
         sudo sed -i 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config
-        sudo yum install -y kubelet-1.7.3-1 kubeadm-1.7.3-1 kubectl-1.7.3-1
+        sudo yum install -y kubelet-1.7.4-0 kubeadm-1.7.4-0 kubectl-1.7.4-0
     elif is_ubuntu; then
         sudo apt-get update && sudo apt-get install -y apt-transport-https
         sudo curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -
-        sudo sh -c 'cat > /etc/apt/sources.list.d/kubernetes.list <<EOF 
+        sudo sh -c 'cat > /etc/apt/sources.list.d/kubernetes.list <<EOF
 deb http://apt.kubernetes.io/ kubernetes-xenial main
 EOF'
         sudo apt-get update
-        sudo apt-get install -y kubelet=1.7.3-01 kubeadm=1.7.3-01 kubectl=1.7.3-01
+        sudo apt-get install -y kubelet=1.7.4-00 kubeadm=1.7.4-00 kubectl=1.7.4-00
     else
         exit_distro_not_supported
     fi

doc/source/setup.rst

@@ -45,8 +45,8 @@ Start installation:
 Setup environment variables for kubectl and openstack client:
 ::
 
-  export KUBECONFIG=/etc/kubernetes/admin.conf 
+  export KUBECONFIG=/opt/stack/admin.conf
-  source openrc admin admin
+  source /opt/stack/devstack/openrc admin admin
 
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